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<div class="title"> Module Documentation: eml-unitTypeDefinitions</div>
</td><td><a class="navlink" href="index.html">Back to EML Contents</a></td>
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<div class="sectiontitle">EML Unit Type Definitions</div>
            
              
<div class="sectiontitle">Philosophy of Units</div>
              
<p>The concept of "unit" represents one of the most fundamental
            categories of metadata. The classic example of data entropy is the
            case in which a reported numeric value loses meaning due to lack of
            associated units. Much of Ecology is driven by measurement, and
            most measurements are inherently comparative. Good data description
            requires a representation of the basis for comparison, i.e., the
            unit. In modeling units, the authors of EML drew
            inspiration from the
            <a href="http://physics.nist.gov/cuu/Units/introduction.html">
            NIST Reference on Constants, Units, and Uncertainty</a>.
            This document defines a unit as "a particular physical quantity,
            defined and adopted by convention, with which other particular
            quantities of the same kind are compared to express their value."
            The authors of the EML 2 specification (hereafter "the authors")
            decided to make the unit element required, wherever
            possible.</p>
              
<p>The units are defined in the 
        <a href="http://www.ch.ic.ac.uk/rzepa/codata2/">STMML language</a> 
        in a document that is shipped with each release of
        EML. See the accompanying STMML file, eml-unitDictionary.xml, for
        precise, quantitative definitions of each of these units and their
        relationships to base SI units</p>
              
<p>which modules use these types (and which could but dont yet?)</p>
              
<p>anything else?</p>
            
          
        
<div class="title">Module details</div>
<table border="0" class="tabledefault" id="eml-unitTypeDefinitions">
<tr>
<td class="tablepanel"> Recommended Usage: </td><td class="tablepanel">any module that needs units</td>
</tr>
<tr>
<td class="tablepanel"> Stand-alone: </td><td class="tablepanel">no</td>
</tr>
<tr>
<td class="tablepanel"> Imports: </td><td class="tablepanel">eml-documentation</td>
</tr>
<tr>
<td class="tablepanel"> Imported By: </td><td class="tablepanel"></td>
</tr>
</table>
<table class="tabledefault" border="0">
<tr>
<td colspan="2">
<h2>Simple Type Definitions:</h2>
</td>
</tr>
<tr>
<td class="tablehead" colspan="2">
<h3>
<a class="sitelink" name="StandardUnitDictionary">StandardUnitDictionary</a>
</h3>
</td>
</tr>
<tr>
<td class="tablepanel"></td><td valign="top" class="tablepanel" colspan="1">
<blockquote>
          
<p>The unitDictionary is the standard set
        of units included with the EML distribution, mainly from the
        SI standard. These unit names should  be used in the standardUnit field to
        describe an attribute. See the accompanying STMML file, eml-unitDictionary.xml, for
        precise, quantitative definitions of each of these units and their
        relationships to base SI units.</p>
          
<p>The standard Unit Dictionary is built from a union of simpleTypes. 
          This construct allows unit types to be used individually as appropriate 
          in EML content (e.g., LengthUnitType for distances )</p>
        
</blockquote>
</td>
</tr>
<tr>
<td class="tablehead" colspan="2">
<h3>
<a class="sitelink" name="LengthUnitType">LengthUnitType</a>
</h3>
</td>
</tr>
<tr>
<td class="tablepanel">
<p>
<span class="boldtext">Derived from: </span><span class="boldtext">xs:string</span> (by xs:restriction) </p>
<p>
<span class="boldtext">Allowed values: </span>
<ul>
<li>meter</li>
<li>nanometer</li>
<li>micrometer</li>
<li>micron</li>
<li>millimeter</li>
<li>centimeter</li>
<li>decimeter</li>
<li>dekameter</li>
<li>hectometer</li>
<li>kilometer</li>
<li>megameter</li>
<li>angstrom</li>
<li>inch</li>
<li>Foot_US</li>
<li>foot</li>
<li>Foot_Gold_Coast</li>
<li>fathom</li>
<li>nauticalMile</li>
<li>yard</li>
<li>Yard_Indian</li>
<li>Link_Clarke</li>
<li>Yard_Sears</li>
<li>mile</li>
</ul>
</p>
</td><td valign="top" class="tablepanel" colspan="1">
<blockquote>
          
<p>The LengthUnitType is the enumerated list of units which are of length type, or have a parentSI of meter. 
        These unit names can be used where ever content should be restricted to a length, such as a distance or 
        altitude. The units are defined in the STMML
        language in a document that is shipped with each release of
        EML called  eml-unitDictionary.xml. See this file for
        precise, quantitative definitions of each of these units and their
        relationships to base SI units.</p>
        
</blockquote>
</td>
</tr>
<tr>
<td class="tablehead" colspan="2">
<h3>
<a class="sitelink" name="MassUnitType">MassUnitType</a>
</h3>
</td>
</tr>
<tr>
<td class="tablepanel">
<p>
<span class="boldtext">Derived from: </span><span class="boldtext">xs:string</span> (by xs:restriction) </p>
<p>
<span class="boldtext">Allowed values: </span>
<ul>
<li>kilogram</li>
<li>nanogram</li>
<li>microgram</li>
<li>milligram</li>
<li>centigram</li>
<li>decigram</li>
<li>gram</li>
<li>dekagram</li>
<li>hectogram</li>
<li>megagram</li>
<li>tonne</li>
<li>pound</li>
<li>ton</li>
</ul>
</p>
</td><td valign="top" class="tablepanel" colspan="1">
<blockquote>
          
<p>The MassUnitType is the enumerated list of units which are of mass type, or have a parentSI of kilogram. 
        These unit names can be used where ever content should be restricted to a mass, such as an amount. 
        The units are defined in the STMML
        language in a document that is shipped with each release of
        EML called  eml-unitDictionary.xml. See this file for
        precise, quantitative definitions of each of these units and their
        relationships to base SI units.</p>
        
</blockquote>
</td>
</tr>
<tr>
<td class="tablehead" colspan="2">
<h3>
<a class="sitelink" name="otherUnitType">otherUnitType</a>
</h3>
</td>
</tr>
<tr>
<td class="tablepanel">
<p>
<span class="boldtext">Derived from: </span><span class="boldtext">xs:string</span> (by xs:restriction) </p>
<p>
<span class="boldtext">Allowed values: </span>
<ul>
<li>dimensionless</li>
<li>second</li>
<li>kelvin</li>
<li>coulomb</li>
<li>ampere</li>
<li>mole</li>
<li>candela</li>
<li>number</li>
<li>radian</li>
<li>degree</li>
<li>grad</li>
<li>cubicMeter</li>
<li>nominalMinute</li>
<li>nominalHour</li>
<li>nominalDay</li>
<li>nominalWeek</li>
<li>nominalYear</li>
<li>nominalLeapYear</li>
<li>celsius</li>
<li>fahrenheit</li>
<li>nanosecond</li>
<li>microsecond</li>
<li>millisecond</li>
<li>centisecond</li>
<li>decisecond</li>
<li>dekasecond</li>
<li>hectosecond</li>
<li>kilosecond</li>
<li>megasecond</li>
<li>minute</li>
<li>hour</li>
<li>kiloliter</li>
<li>microliter</li>
<li>milliliter</li>
<li>liter</li>
<li>gallon</li>
<li>quart</li>
<li>bushel</li>
<li>cubicInch</li>
<li>pint</li>
<li>megahertz</li>
<li>kilohertz</li>
<li>hertz</li>
<li>millihertz</li>
<li>newton</li>
<li>joule</li>
<li>calorie</li>
<li>britishThermalUnit</li>
<li>footPound</li>
<li>lumen</li>
<li>lux</li>
<li>becquerel</li>
<li>gray</li>
<li>sievert</li>
<li>katal</li>
<li>henry</li>
<li>megawatt</li>
<li>kilowatt</li>
<li>watt</li>
<li>milliwatt</li>
<li>megavolt</li>
<li>kilovolt</li>
<li>volt</li>
<li>millivolt</li>
<li>farad</li>
<li>ohm</li>
<li>ohmMeter</li>
<li>siemen</li>
<li>weber</li>
<li>tesla</li>
<li>pascal</li>
<li>megapascal</li>
<li>kilopascal</li>
<li>atmosphere</li>
<li>bar</li>
<li>millibar</li>
<li>kilogramsPerSquareMeter</li>
<li>gramsPerSquareMeter</li>
<li>milligramsPerSquareMeter</li>
<li>kilogramsPerHectare</li>
<li>tonnePerHectare</li>
<li>poundsPerSquareInch</li>
<li>kilogramPerCubicMeter</li>
<li>milliGramsPerMilliLiter</li>
<li>gramsPerLiter</li>
<li>milligramsPerCubicMeter</li>
<li>microgramsPerLiter</li>
<li>milligramsPerLiter</li>
<li>gramsPerCubicCentimeter</li>
<li>gramsPerMilliliter</li>
<li>gramsPerLiterPerDay</li>
<li>litersPerSecond</li>
<li>cubicMetersPerSecond</li>
<li>cubicFeetPerSecond</li>
<li>squareMeter</li>
<li>are</li>
<li>hectare</li>
<li>squareKilometers</li>
<li>squareMillimeters</li>
<li>squareCentimeters</li>
<li>acre</li>
<li>squareFoot</li>
<li>squareYard</li>
<li>squareMile</li>
<li>litersPerSquareMeter</li>
<li>bushelsPerAcre</li>
<li>litersPerHectare</li>
<li>squareMeterPerKilogram</li>
<li>metersPerSecond</li>
<li>metersPerDay</li>
<li>feetPerDay</li>
<li>feetPerSecond</li>
<li>feetPerHour</li>
<li>yardsPerSecond</li>
<li>milesPerHour</li>
<li>milesPerSecond</li>
<li>milesPerMinute</li>
<li>centimetersPerSecond</li>
<li>millimetersPerSecond</li>
<li>centimeterPerYear</li>
<li>knots</li>
<li>kilometersPerHour</li>
<li>metersPerSecondSquared</li>
<li>waveNumber</li>
<li>cubicMeterPerKilogram</li>
<li>cubicMicrometersPerGram</li>
<li>amperePerSquareMeter</li>
<li>amperePerMeter</li>
<li>molePerCubicMeter</li>
<li>molarity</li>
<li>molality</li>
<li>candelaPerSquareMeter</li>
<li>metersSquaredPerSecond</li>
<li>metersSquaredPerDay</li>
<li>feetSquaredPerDay</li>
<li>kilogramsPerMeterSquaredPerSecond</li>
<li>gramsPerCentimeterSquaredPerSecond</li>
<li>gramsPerMeterSquaredPerYear</li>
<li>gramsPerHectarePerDay</li>
<li>kilogramsPerHectarePerYear</li>
<li>kilogramsPerMeterSquaredPerYear</li>
<li>molesPerKilogram</li>
<li>molesPerGram</li>
<li>millimolesPerGram</li>
<li>molesPerKilogramPerSecond</li>
<li>nanomolesPerGramPerSecond</li>
<li>kilogramsPerSecond</li>
<li>tonnesPerYear</li>
<li>gramsPerYear</li>
<li>numberPerMeterSquared</li>
<li>numberPerKilometerSquared</li>
<li>numberPerMeterCubed</li>
<li>numberPerLiter</li>
<li>numberPerMilliliter</li>
<li>metersPerGram</li>
<li>numberPerGram</li>
<li>gramsPerGram</li>
<li>microgramsPerGram</li>
<li>cubicCentimetersPerCubicCentimeters</li>
</ul>
</p>
</td><td valign="top" class="tablepanel" colspan="1">
<blockquote>
          
<p>The unitDictionary is the standard set
        of units included with the EML distribution, mainly from the
        SI standard. These unit names can be used in the standardUnit field to
        describe an attribute. The units are defined in the STMML
        language in a document that is shipped with each release of
        EML. See the accompanying STMML file eml-unitDictionary.xml for
        precise, quantitative definitions of each of these units and their
        relationships to base SI units.</p>
          
<p>The standard Unit Dictionary is built from a union of simpleTypes. This Type 
enumerates the units which are not in other Type definitions, but are to be 
included as standard.</p>
        
</blockquote>
</td>
</tr>
<tr>
<td class="tablehead" colspan="2">
<h3>
<a class="sitelink" name="angleUnitType">angleUnitType</a>
</h3>
</td>
</tr>
<tr>
<td class="tablepanel">
<p>
<span class="boldtext">Derived from: </span><span class="boldtext">xs:string</span> (by xs:restriction) </p>
<p>
<span class="boldtext">Allowed values: </span>
<ul>
<li>radian</li>
<li>degree</li>
<li>grad</li>
</ul>
</p>
</td><td valign="top" class="tablepanel" colspan="1">
<blockquote>
          
<p>The AngleUnitType is the enumerated list of angle units. For example,
            plane angle (radian, rad) and solid angle (steradian, sr) are actually 
            dimensionless, and their symbols used as appropriate 
       (e.g, sr in photometry). These unit names could be used where 
       ever content should be restricted.</p>
        
</blockquote>
</td>
</tr>
</table>
<p class="contact"> Web Contact: <a href="mailto:jones@nceas.ucsb.edu">jones@nceas.ucsb.edu</a>
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